Cardiovascular Flashcards
Myocardial ischemia (Ischemic heart disease)
Myocardial ischemia (Ischemic heart disease)
Local, temporary deprivation of the coronary blood supply
Leads to Anaerobic metabolism production of Lactic acid decrease in Myocardial pH Cell ischemia/death
Can lead to: Stable angina (decrease in O2, lactic acid buildup) Prinzmetal angina (vasospastic), when patient is resting Silent ischemia (asymptomatic, older diabetic women)
Myocardial Infarction
Myocardial Infarction: prolonged interruption of coronary blood flow causing necrosis
“Time = Muscle”
Non-ST Elevation MI
Subendocardial MI—only involving the layer beneath endocardium
ST depression, T wave inversion
Infarction can extend if thrombus lodges permanently into the vessel
STEMI
Infarction through all layers of myocardium, endocardium to epicardium (transmural MI)
ST elevations
Elevated cardiac enzymes
Pain may radiate to jaw, left arm
Treatment: cardiac catheter to break up plaque
Preload
The volume of blood in the ventricles at the end of diastole that the heart must pump w/ each beat
Determined by amt of venous return and degree of muscle stretch. (volume load, right side of the heart)
Afterload
The resistance or pressure the heart must overcome to eject blood from the left ventricle into the aorta. 184/100 BP.
Checking arterial blood pressure (pressure load, left side of heart)
RAS
Renin: Protein released by kidneys when kidneys don’t receive enough perfusion
Angiotensin: Hormone that vasoconstricts so that blood flow to kidney increases.
Aldosterone: sodium and water absorption in kidney/potassium excretion.
These maintain fluid volume, to maintain cardiac output.
Varicose Veins
Veins in which blood has pooled with blood
Appear distended, tortuous, and can be palpable
Usually in the saphenous vein
Frequently seen in individuals who stand for a long time
Nurses, assembly line workers, cashiers
Increased intra-abdominal pressure causes gradual venous distention
S/S:
Edema & aching of the lower extremities
Edema subsides w/ elevation of legs